EARNINGS PER COMMON SHARE (EPS) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator for EPS:
Income (loss) from continuing operations	$ 1,737	$ 294	$ 5,817	$ (5,817)
Less: Net income from continuing operations attributable to noncontrolling interests	70	11	175	78
Less: Preferred stock dividends	7	7	22	22
Income (loss) attributable to AIG common shareholders from continuing operations	1,660	276	5,620	(5,917)
Income from discontinued operations, net of income tax expense	0	5	0	4
Net income (loss) attributable to AIG common shareholders	$ 1,660	$ 281	$ 5,620	$ (5,913)
Denominator for EPS:
Weighted average common shares outstanding - basic	852,765,263	867,713,308	861,211,983	869,627,926
Dilutive common shares	11,254,231	5,417,642	9,790,035	0
Weighted average common shares outstanding - diluted	864,019,494	873,130,950	871,002,018	869,627,926
Basic:
Income (loss) from continuing operations	$ 1.95	$ 0.31	$ 6.53	$ (6.80)
Income from discontinued operations	0	0.01	0	0
Income (loss) attributable to AIG common shareholders	1.95	0.32	6.53	(6.80)
Diluted:
Income (loss) from continuing operations	1.92	0.31	6.45	(6.80)
Income from discontinued operations	0	0.01	0	0
Income (loss) attributable to AIG common shareholders	$ 1.92	$ 0.32	$ 6.45	$ (6.80)
Dilutive shares excluded from computation of diluted earnings per share				4,432,369
Number of shares excluded from diluted shares outstanding because the effect would have been anti-dilutive	5,200,000	70,900,000	6,600,000	68,900,000